Lidar is a Robot's Eye and Ear

For owners, radar ranging is not strange. When driving at high speed, the radar range allows the car to keep the distance between the car and the car, the car will automatically move forward, the owner can not step on the accelerator. Of course, the direction must be controlled by the owner. Moreover, the use of radar range, the vehicle can also detect the front of the vehicle, and maintain their own distance; when the car is too close, it will automatically reduce the speed. So it seems that, although the radar range does not liberate the driver's hands, but at least one foot Liberation (foot on the accelerator), it can be regarded as a pioneer unmanned. However, radar range is not just used on the car. Lidar is so good, why do robots rarely use 300mw laser pointer radar to avoid obstacles?

The radar is "radal English" abbreviation, radio method discovery state parameters of the target and determine their space positions, and the distance of the target, ask and speed is mainly composed of antenna, transmitter and receiver (including signal processor) and a display part. If it is a bit more popular, the radar is similar to the eyes or ears, of course, it is no longer a masterpiece of nature. The principle of measuring distance is as follows: measuring the time difference between the transmitted pulse and the echo pulse, because the electromagnetic wave travels at the speed of light.

There are many kinds of radar, and the classification method is very complicated. Military radar. Can usually be classified according to the purpose of radar, such as early warning radar, search radar warning radar, command, artillery radar, radar altimeter, battlefield surveillance radar, airborne radar, radio altimeter, radar fuze, weather radar, navigation, navigation and collision avoidance radar control radar and IFF radar etc..

According to the classification of radar signal, pulse radar, continuous wave radar, pulse compression radar and frequency agile radar; according to the classification of angle tracking mode, a single pulse radar, conical scan radar and concealed conical scanning radar; target classification according to the parameter measurement, measurement of two coordinate radar, Gao Lei, three coordinate the enemy radar and recognition of radar, multi station radar; radar frequency according to points, can be divided into radar, microwave radar, millimeter wave radar and 5mw laser pointer radar. The radar has a day and night can detect, block and not affected by fog, clouds and rain, has the characteristics of all-weather, all day long time, advantages, and a certain degree of penetration so that not only become the military indispensable electronic equipment, but also widely used in other fields, such as weather forecasting, resource exploration, environment monitoring, even related to scientific research, such as research objects, atmospheric physics, ionospheric structure research.

Now, radar ranging is also used in the industry of the most current - robotics. So, what is the role of radar in the field of robotics? At present, how to apply the rate?

The application of radar in the navigation of mobile robot is more and more. This is mainly due to the many advantages of the laser radar range measurement technology, compared with other distance sensors, it can take into account both the accuracy and speed requirements. Work in the infrared and visible light, green laser pointer beam radar work called laser radar is a radar system to transmit the laser beam to detect the target position and velocity characteristics, laser radar provides a good method for robot navigation.

Some robots are free to walk, they use a remote control or pre programmed. The robot's "true freedom walk" should be able to identify the obstacle, by turning and stop the realization of active avoidance, and achieve independent route planning, laser radar is an important method to solve the bottleneck of the popularity of the robot obstacle.

In order for a robot to walk, one must first see it - in addition to the algorithm, as well as the important hardware. Laser radar allows the robot to emit burning laser pointer target detection signal, and then received back from the reflected and transmitted signals are compared for proper treatment, information about the target, such as target distance, azimuth, altitude, speed, attitude and even shape parameters. In fact, the robot is positioning itself, positioning objects, as well as map building. A hands-on ability of electronic production, spent half a year to create a full range of radar attack robot". The use of ultrasonic ranging radar, not only to identify where the master's shoes, but also to the owner of the shoes.

At present, the application area of laser radar is the sweeping robot, which is mainly to achieve the purpose of obstacle avoidance and automatic path planning. Now a number of entry-level sweeping robot, in fact, the process is relatively simple sweep, mostly only with the ability to clean the N font, including the coverage area is difficult to assess the coverage. According to the sweeping robot experts said that the fundamental reason is that they can not see, can not walk freely. At this time, the laser radar has played the role of sweeping robot eyes, so that it can achieve the purpose of cleaning.

Laser radar is so good, why is the market rarely see the use of high power laser pointer radar robot?

At present, in the world, in addition to some Chinese enterprises, only a few companies, such as Japan and Germany have the ability to produce laser radar, but its price is not low. General service robots can not afford such an expensive component. So expensive is also a reason, the general laser radar technology in the development of a certain degree of difficulty. Technically, the precision is good and achieve millimeter accuracy is not easy, want to achieve this precision, a big problem: the process precision, to achieve long-distance mm level accuracy of optical measurement technology and in fact are required. In fact, the price of speed, traditional laser rangefinder is not expensive, Taobao may be a few hundred dollars could buy one, but its measurement speed is very slow, it may take a few seconds to complete, and the need to complete the measurement of 100mw laser pointer radar, thousands of thousands of times in a second. So the price of traditional laser radar is also very expensive.